In electronic equipment such as a TV receiver, a video recorder, and the like, many electronic circuits are partitioned into and mounted on a plurality of circuit blocks for every function thereof. Although wiring patterns are printed on respective circuit blocks and many circuit components are mounted on the respective circuit blocks, the wiring patterns become complicated because many circuit components are mounted more compactly so that the wiring patterns are hardly seen with the naked eye. Accordingly, the efficiency of an operation such as inspecting the printed circuit board, and the like, is reduced.
To cope with such problems, for example, a first patent literature, i.e. JP 3-63966 U discloses the indication of symbols on a circuit board, provided with a plurality of terminals and copper foil circuits connected to the respective terminals, adjacent to the terminals, and indication of arrows showing a flowing direction of a current and symbols on the copper foil circuits. Further, a second patent literature, i.e. JP 3000794 Y, discloses a printed wiring board having non-segmented patterns for a plurality of types of signals wherein the corresponding types of signals are indicated inside non-segmented pattern areas. Still further, a third patent literature, i.e. JP 2001-339229 A, discloses a phase shifter and a low noise amplifier formed on a substrate wherein band-shaped conductive connection portions are disposed adjacent to each other, respectively, on the phase shifter and the low noise amplifier, and they have short lands for facilitating soldering and through holes for test probes, respectively, at the tip end portion thereof.
Provided that a group of circuit components corresponding to a plurality of circuit blocks are mounted on a printed circuit board, ground patterns are formed on respective wiring patterns corresponding to the respective circuit blocks, and a group of the circuit components are mounted on the printed circuit board as a batch. Accordingly, the respective ground patterns are to be connected to each other, respectively, to be grounded. If the ground patterns of the plurality of circuit blocks are connected to each other, respectively, there is a possibility of the occurrence of an influence upon the circuit operation and influence of noise in the respective blocks. Accordingly, there is needed a confirmation operation for confirming the restraining of such an influence in what manner the circuit blocks are connected to each other, respectively. Meanwhile, although it is needed in such a confirmation operation to identify the ground patterns of the circuit blocks, since the wiring patterns are printed in a very complicated manner, it takes a lot of time to identify the wiring patterns with the naked eye, thereby reducing the operation efficiency.
Although it is considered to indicate symbols and the like on the wiring patterns, as disclosed in the first and second patent literatures, if the ground patterns are very complicated, it is necessary to indicate symbols and the like on the entire ground patterns, which is not realistic. Further, it is considered to form the short lands as disclosed in the third patent literature, a plurality of short lands have to be formed corresponding to the ground patterns if there exist a plurality of ground patterns, making it unable to identify as to which circuit blocks the short lands correspond to, so that an improvement in operational efficiency cannot be expected.